MCQ
Sound waves of wavelength $\pi$ travelling in a medium with a speed of $v\ m/ s$ enter into another medium where its speed is $2v\ m/ s$. Wavelength of sound waves in the second medium is:
- A$\pi$
- B$\frac{\pi}{2}$
- ✓$2\pi$
- D$4\pi$
✓
Answer
Correct option: C.
$2\pi$
When wave passes from one medium to another its frequency $(v)$ does not chang but its velocity and wavelength changs.
$\text{v}=\text{v}\lambda$ or $\text{v}=\frac{\text{v}}{\lambda}$
$\frac{\text{v}}{\lambda}=\frac{2\text{v}}{\lambda_2}\Rightarrow\lambda_2=2\lambda.$
Hence verifies the correct option $(c)$
$\text{v}=\text{v}\lambda$ or $\text{v}=\frac{\text{v}}{\lambda}$
$\frac{\text{v}}{\lambda}=\frac{2\text{v}}{\lambda_2}\Rightarrow\lambda_2=2\lambda.$
Hence verifies the correct option $(c)$
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